Die innere Dynamik der Tieftemperaturphasen des Molekülkristalls CH$_{4}$
Die innere Dynamik der Tieftemperaturphasen des Molekülkristalls CH$_{4}$
Solid methane shows two transition points (90.67 °K > T > 20.55 °K phase $\alpha$, 20.55 °K > T >ca. 8 °K phase $\beta$, T <ca. 8°K phase $\gamma$). The energy distribution of slow neutrons scattered by solid methane at 6.5 °K (transition-region $\beta-\gamma$) and at 2. 7 °K (phase $...
| Personal Name(s): | Dorner, B. |
|---|---|
| Stiller, H. H. | |
| Contributing Institute: |
Publikationen vor 2000; PRE-2000; Retrocat |
| Imprint: |
Jülich
Kernforschungsanlage Jülich, Verlag
1966
|
| Physical Description: |
12 p. |
| Document Type: |
Report Book |
| Research Program: |
ohne Topic |
| Series Title: |
Berichte der Kernforschungsanlage Jülich
476 |
| Link: |
OpenAccess OpenAccess |
| Publikationsportal JuSER |
|
Solid methane shows two transition points (90.67 °K > T > 20.55 °K phase $\alpha$, 20.55 °K > T >ca. 8 °K phase $\beta$, T <ca. 8°K phase $\gamma$). The energy distribution of slow neutrons scattered by solid methane at 6.5 °K (transition-region $\beta-\gamma$) and at 2. 7 °K (phase $\gamma$) is measured by the inverse-filter-method. The results are compared with earlier measurements at 18 °K (phase $\beta$). The spectrum obtained in phase y is in qua.Jitative agreement with a structural model introduced by James and Keenan under the assumption of octopoloctopol interaction. A detailed comparison for phase ß is not presented. In the region of the transition from phase $\beta$ to phase $\gamma$, parts of the observed frequency distribution can be interpreted as components of the pure phases $\beta$ and $\gamma$; some other parts appear only in the transition region. The Debye-Waller factor is calculated from the frequency distribution in phase $\gamma$ and measured in phase $\gamma$ by the elastic scattering of neutrons. The Debye-Waller factor determined in that way indicates that the protons have large amplitudes. |